code: def test_group_by_filter_all_true() -> None:
      df = pl.DataFrame(
          {
              "name": ["a", "a", "b", "b"],
              "type": [None, 1, 1, None],
              "order": [1, 2, 3, 4],
          }
      )
      out = (
          df.group_by("name")
          .agg(
              [
                  pl.col("order")
                  .filter(pl.col("order") > 0, type=1)
                  .n_unique()
                  .alias("n_unique")
              ]
          )
          .select("n_unique")
      )
      assert out.to_dict(as_series=False) == {"n_unique": [1, 1]}
  
file_path: polars/py-polars/tests/unit/operations/test_filter.py
imports: from datetime import datetime
  import pytest
  import polars
  from polars import PolarsDataType
  from polars.testing import assert_frame_equal
label_desc: Use image node_id 4 for calling a global function with example usage: test_group_by_filter_all_true() without return types